Acrylic Canopy / Windows Bolted Joint

[drrabazz]

I am looking for information on bolting an acrylic canopy or window to an airframe. I have seen the edges of the acrylic windows wrapped with fiberglass to provide bearing strength and elastomer bushings used. The end goal is a bushing/material combo (and process) that will provide a published bearing capability without extensive testing. Are there any published processes and analysis methods?

 

[rb1957]

i'd suggest talking to a canopy manufacturer.

otherwise, using an NAS spacer would protect the plastic from clamp-up stresses.

Quando Omni Flunkus Moritati

 

[SuperStress]

Since canopies and windows are often critical for bird strike conditions, I would be surprised if you could qualify any installation purely analytically.

SuperStress

 

[drrabazz]

For this particular test vehicle, and due to the geometry (canopy is overhead and we have a separate windshield) there will be no birdstrike req. That said we will be pressure testing several articles. Manufacturers I've talked to are mostly build to print shops with little experience in design. The joint analysis would be heavily dependent on structural test. What I'm looking for is someone who has been through it before and has a method with values based on test for the joint.

 

[WKTaylor]

RE RB'57's comment...

Use an NAS aluminum spacer with a medium-to-hard rubber tube-sleeve around the OD of the spacer.

Spacer prevents crushing, rubber prevents direct contact between hole and metal spacer... and allows some degree of expansion/contraction.

Drilling acrylic is tricky! Special drill-bit geometry is required for decent holes.



Regards, Wil Taylor

Trust - But Verify!

We believe to be true what we prefer to be true.

For those who believe, no proof is required; for those who cannot believe, no proof is possible.

Unfortunately, in science what You 'believe' is irrelevant – "Orion"

 

[MikeHalloran]

Acrylic also likes kerosene as a drilling lubricant.



Mike Halloran
Pembroke Pines, FL, USA